Undervolting on Linux?

Hello guys,
I got a laptop a few months ago intended to get me outside. Anyway It came with windows (this was before the switch to Linux didnt buy a new laptop for Linux just to be clear) I had it undervolted using intel extream utility on windows and it improved thermals by a good bit as well as battery life is there a way to undervolt on linux in a similar way or just by using the BIOS/UEFI?

EDIT: after looking for a few minites the BIOS does not seem to have any way i can change "overclocking" settings everthing seems to be locked.

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UEFI or BIOS is always the best way to go, no matter the OS

If it is stable on Windows will it be on Linux? from my understanding it shoudnt. a bit nervouse have never really over clocked or underclocked a laptop before (other then intel management thing). if so i may just put in the setting I was using on windows

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Rare edge cases aside - if a processor is stable it doesn't make a difference which program it's executing.

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If it is an off the shelf laptop computer. I would recommend not overclocking it. I seen it where when they overclocked the processor on off the self computer they make it run worst than if they kept it standard. Most of the time it because the instruction coming to the processor from the bus basically can't get there fast enough leads to idle cycles causing more wear.

This is about undervolting, not overclocking.

Lowering the voltage does increase the risk of timing errors. Lowering the voltage is one of the methods for running a glitch attack. Not exactly good for the processor either. That being said i believe Linux does have api calls for it.

How come?

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Potentially relevant


Uses Windows, but I figure you should be able to do the same for Linux
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If you are attempting a side-channel attack on processor or any other types of chips lowering the voltage to cause a glitch is one of the methods. This can cause the instruction to be corrupted( or skip instructions) and depending on what the processor is doing at the time like handling a state the processor can cause it to act weird or damage it. While it is a low chance of occurring and causing damage if you perform a power glitch enough times it will screw something up. On the Motorola MC68HC05B6 low-voltage power glitch results in corrupted EEPROM data read.

Yes, undervolting can of course interfere with instructions and corrupt data, because the CPU is basically overclocked for the given voltage. I just don't see how the CPU could possibly be damaged by it. Got any links?

Alright I Do not think i am going to at this point, for more than just the reasons you have mentioned also because the bios dose not seem to have anyway to change voltage setting and sould ranther do it by the bios than random software.

This is already planed, it isn't thermal throtting; however when I had it undervolted useing the intel utility, i seems to get about an 1~2 hours more battery life under normal use. The other reason was it was able to stay at max boost clock under nearly all stress test. Pretty big bump in proformance. Anyway thermal paste will help with boost clock I know but would it help battery?

is it any more dangrous than an overclock on a desktop? I had always thought underclocking is more or less safe as long as it was modest.

I would like to know this as well. I always thought it wasn't a very big deal as far as damage, i know it is less stable.

It is at your risk, so just make sure you don't go overboard with undervolting

If you are trying to get better battery performance on Linux, trying looking if your distro has the laptop project

https://wiki.archlinux.org/index.php/TLP

https://linrunner.de/en/tlp/tlp.html

Yes it does(arch) I have had it for last 4ish days. It helped out a good bit, just going to replace the thermal paste see where that leaves me.

Yeah paste might help with the clock and thermals, not sure about the battery tho

I don't know for sure if replacing the thermal paste will increase battery life or help the battery, but logically I would think it will not. @perkelator if changing the thermal paste does improve the battery would you please post your results. I am very interested in that subject.

@darkhorseman91 This is the first time I've heard that undervolting might damage your component(s). I've always heard quite the opposite that it should increase the lifespan of your component(s) since it reduces wear.

I honestly do not think it will, it will be 2 or 3 weeks before I change it, doing research on what the best thermal paste is for laptops.

Same I thought it was better to do or like negligible

I should mention that most time i am actually causing glitches with under voltage I am directly accessing the pins. and excerpt for the a book can be found here. For it the actually occur multiple items on the processor, power supply, and motherboard would have to fail. Normally Brownout Reset Interrupt will reset the processor state to prevent damage and it is rare for a processor not that low voltage detection.